Silverface Princeton Non-Reverb

This Princeton looks to be pretty much untouched aside from a three-prong power cord/outlet. Power tubes are old... it's not very loud but stays clean all the way up. I tried some 6L6's in it and it was much louder. Can anyone tell me what year/circuit this is?

Here's more pics, by my research this looks to be a 1980. Didn't know they made them that late. The volume is not a pull pot. Did they change the circuit on these or is it the same as the blackface Princeton NR's?

Put an Eminence Ragin Cajun speaker in today. Wow, it really opened up this little amp! I thought everything sounded pretty good before but now I realize how brittle the stock Oxford really sounds, especially when pushed. Now I've got a nice creamy overdriven sound along with improved clarity and headroom for clean. What a great $45 upgrade!

I can't help you with the year or anything, but that is a sweet little amp. I like it.

your amp is from 1980 (FO+5 digits = 1980).. AB1270 (the classic charts for serial codes end at '79)

cathode bias caps have been changed. Dont just stick 6L6's in a princeton or your can ruin
your transformer.. The amp needs to be rebiased in order to run 6L6s in place of the 6V6s.. although its an okay
thing w/ the 6L6's as long as you put the solid state rectifier plug in there.

Pull boost was added in 1970.. if its not there then its been modified. 3 prong outlet was '78

tvthewiredturtle wrote:

Pull boost was added in 1970.. if its not there then its been modified. 3 prong outlet was '78

Interesting that a correct 1980 pot was used to mod it to non-pull boost. Did they _always_ have the pull boost?

well I'm wondering if that pull boost has nothing to do with the Princeton Amp and everything
to do with the Princeton Reverb. If history is correct.. very little happened to the non reverb
amps all the way back to the 6G2. the AA964 I believe got a change up in the tone stack and
stiffer filtering along with the GZ34 rectifier tube that used to be a 5Y3.
The later models were switched over to the 5U4G rectifier tube.

purist will argue that a true brownface circuit it totally different sounding than the early blackface.
Personally the 6G2 only sounded cool cranked up.

tvthewiredturtle wrote:

Personally the 6G2 only sounded cool cranked up.

I think a few bands in recording sessions agree with that statement. Wasn't a 6G2 one of Billy Gibbon's main studio amps? I think Clapton, Duane Allman, and etc used a 6G2 as well...along with other small chewy amps